AFN Tensioner: Questions and Answers

Hello.
As you know, the timing belt broke on my car at 67,000 km. Now I've taken a _close_ look at my old tensioner pulley. It looks very good overall. However, the edge facing the engine is only 1.80 mm thick, while the other edge is 2.50 mm. Are the edges of the same thickness when new? I can't easily access my new tensioner pulley right now. What could be the reason for this uneven wear, and what would be the appropriate solution?
Thank you!

Hello,

Of course, the bearing surfaces of the tensioner are equally strong.
The problem of timing belts starting to slip on one side in the AFN engine is a known issue.
Measure the width of your timing belt if possible. I suspect it has worn down much more than the tensioner and is therefore torn. The minimum acceptable width is 23 mm (new: 25 mm).
That's what my question was referring to in your other thread.
My first timing belt lasted for 94,000 km without any problems. The second one is currently at about 60,000 km and has a wear of approximately 24 mm.
If the timing belt failures in AFN engines are indeed all due to (excessive) edge wear, which I'm starting to suspect, then it shouldn't be a problem to drive the timing belt for over 90,000 km if it's regularly inspected and the thickness is still above 23 mm, as originally intended.

Best regards,
Albrecht.

I would have to rummage through the depths of our trash can to see if I can still find the ZR, but that probably won't look good. In any case, I will definitely keep a close eye on the ZR now. Is there a way to optimize the ZR somehow? A colleague at work also has the 110 HP TDI in his Seat Leon (which is probably a different engine code). He doesn't care about the technology and has already driven over 120,000 km with his first ZR. That's what I call unfair.

For optimization purposes, please check the error database. There's a factory instruction regarding this issue, supposedly from someone named Michael II.
It's probably best to check the belt every 5,000 kilometers.

By the way, the newer 110 hp TDI engine has a different belt routing system; it's unclear whether this is an improvement.

Best regards,
Albrecht.

I read the article in the error database. My car's manufacturing date is November 1998. The improvements mentioned should have already been installed by then.

Hi,

I've now put 80,000 kilometers on the second one. The width of 24.x is still okay, but what I'm closely monitoring is the condition of the inside of the timing belt; that's concerning me.

But I also think that with inspections every 5,000 miles, I can detect any developing damage in time.

Let's see if I'm right. I plan to drive a bit longer with him.

Mine is from 11/98, and there's no evidence of uneven wear.

I once saw a collection of images showing damage caused by 'ZR' (likely referring to a specific type of incident or equipment), but I can't find it anymore. Does anyone have a link to it?